Use google adword tools
its better to use google keyword and select keywords based on the based on count that has been used in last month
Use google adwords + google trends.
Google Keyword Tool is very cool. It is result-oriented. It gives you the past trend very well. It also gives you suggestions.
Google keywords tool is very helpful, but in the end its still up to the human brain to decide what to keyword to use.
Well, i think you should target different keywords during different stages.
At the beginning of SEO:
At this stage, choose one or two lower-competitive keywords for optimizing a single page.
In the middle period of SEO:
You can turn to optimize for some hot keywords since you have already had a number of contents in your site.
In the latter period of SEO:
It’s time to challenge the most popular keywords. It doesn’t matter if the result is not as expected as it can also boost your ranking you have got in the mid-SEO.
i use google adword, it help me a bit…but if you find an alternative is better:)
What is your niche. If its related to product promotion as affiliate, you could be in for some heavy competition with popular keywords. In such a case its better to first spend time researching the available content on Paid Ad Campaigns and start out with caution. Google adwords keyword tool will get you started with keywords in your niche and their CPC, Volume searched Monthly and lots of relevant info.
Organic keyword building that gets high PR with SE’s is a gradual process, end result of quality content development, proper SEO, from identifying non competing high prospect keywords, proper inclusion of main keyword in your URL, Title and Description Meta Tags, Keyword Density analysis… (beware of penalties associated with excessive keyword stuffing on single page).
Checkout the Competing sites ranked highly for your niche…
I been using Google keyword tool and I know its the best around.
Check this website it will help you
http://www.tech-faq.com/find-keywords.shtml
Google Adwords Keywords Tool
Just whack it into google and you’ll find it, probably the first link. It’s great to find brilliant keywords. 